Study drawings have been used by most famous painters from past and present as a means to ensuring a high level of quality in the final composition - be it in oils, watercolours or even sculpture. Time spent at this stage would save so much more later on, just as with any planning stage. Many required a precision within their work which was only possible by using the right process, from start to finish. Max Ernst differs in this regard, though. Yes, he was a highly skilled draughtsman, of that there can be no doubt, but this was an artist who positively wanted to avoid precision and clarity within his work. He wanted each final painting to have an element of chance about it, something that could not be created identically again. His surrealist content was deliberately unclear in its symbolism, leaving academics to consider a variety of explanations for each addition. As such, he did not require drawings to achieve consistency between artworks and his own ideas. Instead, he used them for other purposes.
Frottage is the most famous invention of Max Ernst, one of several artistic techniques that he created during his career. Many were taken up by other artists in later generations. Frottage involved the artist rubbing loosely with a crayon or pencil over the main surface of the piece, normally a canvas. Underneath he would be holding items such as leaves or other textured objects and their imprint would then appear, magically, on the working area. In this regard, they can be seen as drawings or traces, though would normally become part of a larger oil painting and would then be regarded as part of that artwork, rather than included here within the purely drawn pieces that you find below. Ernst also produced whole series of illustrations for various printed publications and this is perhaps how he is most famous in terms of his talents as a draughtsman - they also provide an additional string to the considerable bow of his ouevre.
In terms of his illustrations for published books, many were for authored work by Paul Éluard. These included Répétitions, Les malheurs des immortels and Au défaut du silence. Others were for novels in the late 1920s / early 1930s such as La femme 100 têtes and Une Semaine de Bonté. The artist himself would eventually write his own books and, naturally, provide all of the illustrative work for those too. As late as the 1970s, right at the end of his career, Max Ernst started to produce lithographs and etchings too. He never really stopped experimenting and achieved an impressive level of quality across a large number of different mediums. Nature and the animal world featured prominently within his work, but most choices would be related to the passage of literature around which his designs were spread. This was, after all, the 20th century, when creativity, expression and experimentation were the key elements in the art world, such as found with the likes of Jackson Pollock, who tried out all manner of different techniques in order to work with line, form and colour using a variety of different mediums.
Traditionally, exhibitions in the major art galleries of the world would only really focus on the main specialisation of each artist, but in recent years there has been a greater effort to provide to visitors a more rounded, comprehensive display of an artist's career. This is very much the case with Max Ernst, as all of the different mediums in which he was involved were closely linked together, and so to only include his paintings in any display would not allow us to understand the full process of his work, nor how he worked new ideas into later artworks. Thankfully you can often see items side by side, drawings and paintings, with a clear visual connection as to how one would have led to the other and one of the upsides of this approach is that it will encourage more art students to concentrate on developing their qualities as draughtsman, having seen how it can inspire and benefit their work in other mediums just as it did for the great modern masters.
The majority of modern artists would have been trained in traditional artistic styles, as drawing would have been a particularly key part of that - introduced almost before anything else is even discussed. All these centuries later and the methods of a draughtsman are still seen as fundamental to the success of any artist, whichever medium they then later specialise in. During the Renaissance era one could not be accepted as a genuine artist unless you could draw, particularly within Italy and later France, but over time art critics have become a little less judgemental and now it is just seen as an important tool which can aid your understanding of most other mediums. For example, painters will invariably draw studies on paper prior to commencing each painting itself. Additionally, many of the best sculptors will study the human body through drawing, in order to learn the many intricacies of the human body that they will then attempt to convey within the three dimensional form in whatever material they choose.
In terms of related artists, one of the most memorable would have to be Wassily Kandinsky, a Russian painter who moved to Germany. Kandinsky drawings perfectly fit the most famous style from his career, which was lines and shapes in harmony with a carefully selected palette. One can see similarities between his work and the Max Ernst drawing listed here. There is a precision, almost akin to an engineering or architectural plan. Kazimir Malevich drawings also have some similarities to that, but were perhaps more expressive and less precise in terms of angles and straight lines. Aside from these two, most 20th century painters have a number of drawings left over from their careers but it is only recently that efforts have been made to protect and document them, as well as potentially including them within catalogue raisonnes of the artist's career, when previously they may have been left out entirely.